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US4752840A Expired / Lapsed US ⏱️ 0.0 years remaining

Multitrack magnetic recording and reproducing device

Assignee: Sharp Corp
•
Filing: 1987-06-22
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Granted: 1988-06-21
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Expires: 2007-06-22
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Abstract

Abstract A multitrack magnetic recording and reproducing device of the type, which converts analog signals into digital signals and records and reproduces such converted data by splitting onto a plurality of tracks, comprises heads for both high and low recording densities such that track pitches corresponding to them are at an integral ratio. It includes a reproducing circuit having detecting-decision making means such as multiplexers which, when information recorded by a head for lower recording density is reproduced by corresponding heads for higher recording density, is adapted to determine whether any of the outputs from these heads is incorrect.

Inventors

  • 👤 Hiromi Juso
  • 👤 Kengo Sudoh
  • 👤 Yukihiko Haikawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 18:09
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02; G11B5/09; G11B20/00; G11B20/10; G11B20/10527; G11B20/18; G11B20/1806

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 237 words
In a multitrack magnetic recording and reproducing device which comprises heads for lower and higher recording densities, ratio of said higher recording density to said lower recording density being an integer greater than 1, and is adapted to convert analog signals into digital signals and to record converted signals by splitting onto a plurality of tracks, a reproducing circuit with error-detecting means comprising a first error detection circuit which receives a first demodulated output signal from one of said tracks and to output a first indicator signal indicating whether said first demodulated output signal is correct or incorrect, a second error detection circuit which receives a second demodulated output signal from another of said tracks and to output a second indicator signal indicating whether said second demodulated output signal is correct or incorrect, a first multiplexer which receives said first indicator signal and transmits said first demodulated output signal if said first indicator signal indicates correct and no signal if said first indicator signal indicates incorrect, a second multiplexer which receives said second indicator signal and transmits said second demodulated output signal if said second indicator signal indicates correct and no signal if said second indicator signal indicates incorrect, and a third multiplexer which receives said first and second indicator signals and transmits said first demodulated output signal, said second demodulated output signal or no signal, depending on the combination of said first and second indicator signals.
Claim 2
Dependent Claim 237 words
In a multitrack magnetic recording and reproducing device which comprises heads for lower and higher recording densities, ratio of said higher recording density to said lower recording density being an integer greater than 1, and is adapted to convert analog signals into digital signals and to record converted signals by splitting onto a plurality of tracks, a reproducing circuit with error-detecting means comprising a first error detection circuit which receives a first demodulated output signal from one of said tracks and to output a first indicator signal indicating whether said first demodulated output signal is correct or incorrect, a second error detection circuit which receives a second demodulated output signal from another of said tracks and to output a second indicator signal indicating whether said second demodulated output signal is correct or incorrect, a first multiplexer which receives said first indicator signal and transmits said first demodulated output signal if said first indicator signal indicates correct and no signal if said first indicator signal indicates incorrect, a second multiplexer which receives said second indicator signal and transmits said second demodulated output signal if said second indicator signal indicates correct and no signal if said second indicator signal indicates incorrect, and a third multiplexer which receives said first and second indicator signals and transmits said first demodulated output signal, said second demodulated output signal or no signal, depending on the combination of said first and second indicator signals.
Claim 3
Dependent Claim 62 words
The device of claim 1 wherein said reproducing circuit further comprises a first buffer memory for temporarily storing said first demodulated output signal and transmitting said first demodulated output signal to said first and third multiplexers, and a second buffer memory for temporarily storing said second demodulated output signal and transmitting said second demodulated output signal to said second and third multiplexers.

References Cited (Backward Citations)

US30482A Cited
USRE31166E Cited
US3761903A Cited
USRE30482E Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-06-21 1991-12-21 1992-06-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-06-21 1995-12-21 1996-06-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-06-21 1999-12-21 2000-06-21 $7700.00 Window Closed / Lapsed

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